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Energy Technologies Scenarios to 2050

3. What must be done in different sectors to substantially reduce CO2 emissions?

  • 3.1 Buildings and appliances
  • 3.2 The power sector
  • 3.3 Transport
  • 3.4 Industry

The source document for this Digest states:

Energy efficiency trends

Big improvements are needed compared to recent energy efficiency trends. Energy efficiency in OECD countries has been improving at just below 1% per year in recent times. A sharp decline from the rate achieved in the years immediately following the oil price shocks of the early 1970s. The ACT Map scenario requires sustained global energy efficiency improvements of 1.4% per year and the BLUE Map scenario calls for 1.7%. While these percentage differences may seem small, the difference of 0.3 percentage points between ACT Map and BLUE Map results in 1,544 Mtoe of additional final energy savings in 2050, 20% of total world final energy use today.

The technology revolution

In both ACT and BLUE scenarios, energy efficiency improvements in buildings, appliances, transport, industry and power generation represent the largest and least costly savings. Next in the hierarchy of importance come measures to substantially decarbonise power generation. This can be achieved through a combination of renewables, nuclear power, and use of CCS at fossil fuel plants. Whichever the final target, action in all these areas is urgent and necessary. It is particularly important to avoid lock-in of inefficient technologies for decades to come. In the BLUE Map scenario, higher-cost options such as CCS in industry and alternative transport fuels need to be deployed. Figure ES.2 shows the sources of CO2 savings in the BLUE Map scenario compared to the Baseline scenario. Policy makers should remember that long lead times are frequently required to implement changes and that priorities in each country will vary according to national circumstances. Reducing energy sector methane emissions, moreover, is also an important part of an overall climate change strategy, as these emissions offer significant near-term and cost-effective greenhouse gas reduction opportunities.

Source & ©: IEA,  Energy Technology Perspectives 2008 :
Scenarios and strategies to 2050. Executive Summary. (2008)
, The technology revolution. p.4. Energy Efficiency Trends. p.7

3.1 Buildings and appliances

The source document for this Digest states:

The ACT scenarios can become reality using technologies for buildings and appliances widely available today and economically viable on a life-cycle cost basis. But the BLUE scenarios call for new and emerging technologies; in some cases technologies will be required that are only economic at relatively high CO2 reduction costs, at least when initially deployed. Widespread conversion of buildings to very low energy consumption, and even “zero” energy buildings, are part of the scenario. The policy implications for efficiency standards for buildings and appliances are huge. A combination of building-shell measures, heat pumps, solar heating and highly efficient appliances and lighting reduces energy needs in buildings as well as shifting fuel use to renewables and low-carbon electricity. USD 7.4 trillion of additional investment in residential and service sector buildings is needed for the BLUE Map, against USD 2.6 trillion for the ACT Map scenario.

Source & ©: IEA,  Energy Technology Perspectives 2008 :
Scenarios and strategies to 2050. Executive Summary. (2008)
The technology revolution. p.5.

3.2 The power sector

The source document for this Digest states:

CO2 capture and storage for power generation and industry is the most important single new technology for CO2 savings in both ACT Map and BLUE Map scenarios, in which it accounts for 14% and 19% of total CO2 savings respectively. BLUE Map includes higher-cost applications of CCS for industry and gas power stations. There is a massive switch to renewables for power generation, especially to wind, photovoltaics, concentrating solar power and biomass. By 2050, 46% of global power in the BLUE Map scenario comes from renewables. Application of all renewable technologies combined, across all sectors, accounts for 21% of CO2 savings in the BLUE Map scenario against the Baseline scenario. A substantial switch to nuclear contributes 6% of CO2 savings, based on the construction of 32 GW of capacity each year between now and 2050. Nuclear accounts for nearly one-quarter of power generation in BLUE Map and hydro for half as much, building on the important role both technologies already play in the Baseline scenario. Figure ES.3 illustrates the annual rates at which new power generation capacity would need to be added in each scenario.

A broad range of scenarios for power generation are considered, from which it can be seen that considerable flexibility exists for individual countries to chose which precise mix of CCS, renewables and nuclear technology they will use to decarbonise the power sector. Total additional investment in the power sector (excluding transmission and distribution) amounts to USD 0.7 trillion in the ACT Map scenario and USD 3.6 trillion in the BLUE Map scenario. These investment figures are the net result from combining higher capital costs per unit of capacity with a one-fifth reduction in electricity production due to end-use electricity savings. Substantial early retirement of capital stock occurs in the BLUE scenarios. For example, one-third of all coal-fired power plants not suitable for CCS will need to close before the end of their technical life. It is recognised that this will be a large step for countries heavily reliant on coal, but a necessary step requiring careful management.

Source & ©: IEA,  Energy Technology Perspectives 2008 :
Scenarios and strategies to 2050. Executive Summary. (2008)
The technology revolution. p.5.

3.3 Transport

The source document for this Digest states:

Major improvements in the efficiency of conventional
										vehicles are needed.
Major improvements in the efficiency of conventional vehicles are needed.

In the ACT Map scenario, energy and emissions in the transport sector are saved largely through major improvements in the efficiency of conventional vehicles and through the increased penetration of hybrids. Low-carbon footprint biofuels play a part, principally as a replacement for gasoline to fuel cars. It is essential to curb the current trend towards larger, heavier vehicles.

The BLUE Map scenario is very challenging for the transport sector and requires significant decarbonisation of transport, which is likely to be costly in a sector dominated by oil products and the internal combustion engine. Low-carbon biofuels are expected to play a significant role in the BLUE Map scenario, within the limits of sustainable production and cropping. Trucks, shipping, and air transport are the chief users of biofuels, since other nonhydrocarbon options are likely to be very expensive to apply to these transport modes. While electric batteries and hydrogen fuel cells are the main alternatives for cars, it is difficult to judge at this stage which of these technologies – or which combination of them – will be the most competitive. Based on fairly optimistic assumptions about technology progress and cost reductions, electric and fuel cell vehicles are expected to cost around USD 6 500 more in 2050 than conventional vehicles. In the BLUE Map scenario, nearly one billion electric and fuel cell vehicles need to be on the roads by 2050. Transport represents the largest single area of investment in the scenarios. Additional investment needs in transport are USD 33 trillion in BLUE Map and USD 17 trillion in ACT Map.

3.4 Industry

The source document for this Digest states:

Directly or indirectly, manufacturing industry accounts for more than one-third of global energy use and CO2 emissions. The iron and steel, and cement industries represent roughly half of industry’s emissions; chemicals and petrochemicals are the other very large sources. Heavy industry has a good record of energy efficiency gains in recent years, driven by the need to manage energy costs. But substantial potential exists for further efficiency gains, especially in less energy-intensive industries, notably through more efficient motor drive systems and combined heat and power. Potential also exists for technology advances that are specific to each industry and for application of CCS.

Very large reductions in CO2 emissions from industry are hard to achieve. In the ACT Map scenario, energy-related CO2 emissions from industry are 63% higher in 2050 than in 2005. In the BLUE Map scenario they are 22% below today’s level, largely reflecting the widespread application of CCS at large, energy intensive plants. Direct and indirect CO2 savings in the BLUE Map scenario are substantial, at nearly 10 Gt of CO2 per year. The BLUE Map scenario requires additional investment over the Baseline of USD 2.5 trillion in the upgrading of industrial plant – mainly in the steel, cement, and pulp sectors – and for increased deployment of CCS.

Source & ©: IEA,  Energy Technology Perspectives 2008 :
Scenarios and strategies to 2050. Executive Summary. (2008)
The technology revolution. p.7

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